Statistical model for MIMO propagation channel in cavities and random media

We present a physics-based channel matrix that establishes the connection between electromagnetism and information theory. The approach is based on impedance matrices and related to the scattering matrix formulation. Cavities and random media support a wave chaotic behaviour that yields an exponential proliferation of multiple paths due to the presence of multiple reflection or scattering. It is shown that fading can be included using the random coupling model (RCM). This model leads to theoretical and numerical predictions of the probability density function of the mutual information in large and complex electromagnetic environments. The effect of losses and modal density on channel capacity can thus be explored and channel hardening bounds quantified.